Packing device



Dec. 15, 1953 w. D. PUTNAM 2,662,659

PACKING DEVICE Filed Feb. 25, 1951 INVENTOR Mu mm 0001.2 y par/1mm Patented Dec. 15, 1953 PACKING DEVICE William Dudley Putnam, Brantford, Ontario, Canada Application February 23, 1951, Serial No. 212,253

3 Claims.

This invention relates to packing devices for frangible articles and more particularly to an egg packing tray.

The invention represents an improvement on the conventional moulded pulp tray which is well known in the art and which essentially consists of a sheet of pulp or other material which is moulded to form a series of hollow conical projections depending below the mean plane of the sheet and a series of conical hollow projections extending above the mean plane of the sheet. The projections above the sheet are disposed diagonally between the projections below the sheet to the end that when the trays are stacked in successive layers in an egg crate the eggs, disposed in the pockets formed by the depending hollow conical projections, overlap each other in a vertical plane. Egg packing trays of this type provide abundant space endwise of the egg to accommodate over-size eggs but laterally of the egg, in the area of its largest diameter, there is very little extra space provided to accommodate oversize eggs. Heretofore the natural resiliency of the conical posts was sufficient to meet the problem and excessive breakage did not occur.

However relatively recent advances in breeding have resulted in an increase in the size of eggs so that eggs once considered oversize are now more nearly normal and it has been found that increased breakage, as a result of the larger eggs being commonplace, presents a serious question to the industry. It is apparent that very difficult and expensive problems would arise if the industry attempted to solve the difiiculty by merely increasing the size of the egg packing trays and crates and the present invention is directed to providing a tray having the same overall dimensions with improved pockets adapted to receive larger eggs than was heretofore possible.

The invention contemplates concave surfaces formed on the substantially conical, hollow posts at the areas adjacent to pockets formed by the hollow conical projections depending below the main plane of the sheet. Thus the marginal confines of each pocket at a level at approximately the medial area of the posts have been increased at four planes to permit the egg to rest lower in the pocket. It has also been noted that the pulp fibres seem to be more easily stretched and distorted under pressure on the concave surfaces than on the normal curvature of the posts, probably because of the change in contour. Thus the area of the egg pocket is increased and the surfaces of the posts which are in contact with the 2 eggs are rendered more resilient and less likely to crack the egg shell when the eggs are crated.

In addition the distance between the marginal rows of posts and the side edges of the tray has been decreased to permit a slightly greater distance, approximately one-sixteenth inch, between the post centers and thus provide a greater pocket area throughout.

In the drawings which illustrate the embodiment of the invention;

Fig. 1 is a fragmentary top plan view of the improved egg tray illustrating the disposition of the pockets, posts, and more particularly, the concave surfaces on the posts.

Fig. 2 is a sectional view through a vertical section line taken substantially on the line 2-2 of Figure 1.

Fig. 3 is a sectional view through a vertical section line through two trays in stacked arrangement taken on a diagonal such as indicated in the line 33 of Figure 1.

Referring more in detail to the drawings in which similar reference characters designate corresponding parts throughout the several views it will be seen that the egg trays l0 consist of any suitable material such as pulp which is moulded to provide rows of symmetrically disposed hollow,

conical cavities depending from the mean planeof the sheet to form pockets I l and rows of symmetrically disposed, conical hollow projections upstanding from the mean plane of the sheet to form posts I2. The said posts are in staggered relationship with respect to the said pockets so that an egg, disposed in any one pocket, is bounded by four posts in equi-spaced arrangement.

It will be apparent that the undersides of the posts l2 form pockets 13 in reverse relationship to the pockets H and the entire trays are so formed that when each succeeding tray is turned relative to the adjacent trays above or below, the pockets ll register with the pockets [3 to provide a plurality of individual egg receiving receptacles as seen most clearly in Figure 3. The egg is inserted with the smaller end downward in the pocket I I and rests against the pocket wall and posts so that at no time is there endwise contact between the egg and tray and similarly the larger end of the egg rests against the walls of the pocket l3 without endwise contact between the egg and tray.

The conventional receptacles embrace ideally what were heretofore considered to be normal eggs and occasional oversize eggs did not present undue difficulties. The present, larger, eggs take up too much space in each receptacle, however, and because of their close, overlapping relationship it has been found that when the crate cover is nailed down excessive pressure occurs and breakage results to such a degree that the loss has assumed serious proportions.

To overcome the problem the present invention provides additional space in each receptacle laterally of the egg in the region of its maximum diameter which is in the neighborhood of the medial area of the posts I2 when the egg is disposed in the pocket II. The posts I2 are moulded in dies which are shaped to provide concave areas hereinafter referred to as depressions It on the posts I2. It will be apparent that to obtain the maximum advantage each post will have a depression I4 at that portion of its surface adjacent to a pocket II and therefore each post in from the margin of the tray will have four depressions I4 formed thereon and each marginal post will have one or two depressions formed thereon depending entirely on the number of pockets I I which it bounds. Similarly each pocket II is bounded by four posts, each of which has a depression I4 formed therein to increase the lateral area of the receptacle. The depressions preferably reach a maximum depth of approximately one-sixteenth inch so that the total diameter of the receptacle at the plane determined is increased by approximately oneeighth inch. Thus more room has been provided at the critical area of the receptacle without increasing the overall dimensions of the egg tray.

It also appears that the depressions M on the post I2 stretch and distort more readily under pressure than the normal curved wall now commonly employed and that as a result, even when the eggs are subjected to such pressure that they press against the depressions I4 less breakage will occur than would normally be the case.

It will be observed that each depression it of the outer surface of the post I2 forms a coincidental protuberance on the inner surface of the post I2, i. e. in the reverse pocket I3 and it might be considered that the advantage gained in the lower pocket II is lost in the upper pocket It. It has been observed however that the portion of the egg which extends into the upper pocket portion of the receptacle is on a receding curve and is apparently not affected by the pressure conditions which are set up when the eggs are crated as the breakage occurs in the lower area of the egg, that is to say in the pocket EI and adjacent thereto in the area about the mean plane of the sheet.

In the present embodiment of the invention the depressions I4 are substantially elliptical but it will be appreciated that they may take any shape and may be of various depths provided that the maximum spatial advantage is gained in the required area.

In addition the marginal areas of the trays between the edges and the posts have been decreased to permit the posts to be spaced onesixteenth of an inch further apart from center to center, thus providing additional space in a lateral plane in the pocket area.

While the preferred embodiment of the invention has been disclosed in association with moulded pulp trays it will be understood that minor variations may be resorted to and the inventive concept may be adapted to other trays all within the spirit of the invention as defined in the appended claims.

claim:

A moulded pulp egg tray which is characterized by a series of spaced hollow post formations extending upwardly of one face of the tray and series of spaced hollow post formations extending downwardly of the opposite face of the tray, said upwardly and downwardly extending post formations being arranged in alternate rows in the lateral direction and presenting egg receiving pockets opening in opposite directions, the upwardly extending post formations being spaced around the upwardly opening pockets formed by the downwardly extending post formations and having downwardly directed outwardly tapering outer wall surfaces with the lower portions thereof merging into the upwardly tapering inner wall surfaces of adjoining downwardly extending post formations and cooperating therewith to provide enlarged pockets for receiving the lower ends of eggs positioned therein, with the eggs projecting above the uppermost extremities of said upwardly extending post formations and into the downwardly opening pockets formed by upwardly extending post formations of a like tray positioned in stacked relation thereabove, and said upwardly extending post formations each having indented portions deforming the walls thereof in the direction of the vertical axis of said post formations and each indented portion extending downwardly from the neighborhood of the medial area of said post to a point short of the point of contact of the inner surface thereof with the upper end of an egg positioned in an upwardly opening pocket in a like trav positioned in stacked relation beneath the same, said indented wall portions providing supports for engaging substantial circumferential areas of th egg surface adjacent but terminating short of the lower end of the whereby to provide increased egg room for the lower end of the egg in the lateral area between the upwardly extending post formations and immediately above the upwardly opening pockets without decreasing substantially the effective egg room provided by the downwardly opening pockets.

2. A moulded pulp packing tray for eggs comprising spaced rows of downwardly extending posts forming a plurality of conical egg receiv ing pockets each of which has a flattened base, a plurality of upwardly extending conical posts disposed immediately adjacent to and in alignment with diagonally related pockets, each of said upwardly extending posts having the outer sides merging at the bottom into the inner sides of the adjacent downwardly extending posts so that the outer surface of each of said upwardly extending posts cooperates with the inner surfaces of adjacent downwardly extending posts to provide pockets for receiving the lower ends of eggs positioned therein, the tops of each of said upwardly extending conical posts being flattened to abut the flattened bases of the downwardly extending posts of a like tray arranged immediately above said tray, each of said upwardly extending posts having concave depressed areas diagonally disposed in the curved outer surface thereof, said concave depressed areas affording four point resilient support for the lower portion of an egg inserted within one of said egg receiving pockets and being adapted to maintain said egg spaced from the base of its pocket, the protuberances on the interior surfaces of the upwardly extending posts corresponding with said concave depressed areas being disposed above the points at which the upper surfaces of eggs in a like tray immediately beneath said tray recede inwardly away from said interior surfaces.

3. A moulded pulp packing tray for eggs comprising spaced rows of downwardly extending posts forming a plurality of conical egg-receiving pockets each of which has a flattened base, a plurality of upwardly extending conical posts disposed immediately adjacent to and in diagonal alignment about the individual pockets, each of said upwardly extending posts having downwardly directed and outwardly tapering sides merging into the upwardly directed, outwardly tapering sides of the downwardly extending posts, the tops of each of said upwardly extending conical posts being flattened to form abutment stops, each of said upwardly extending posts having depressed areas diagonally disposed in the curved outer surface thereof, said depressed areas aifording four point resilient support for the lower portion of an egg inserted within one of said egg-receiving pockets and being adapted to maintain said egg spaced from the base of its pocket, the depressed areas extending from the neighborhood of the medial area of the posts to about the mean plane of the tray.

WILLIAM DUDLEY PUTNAM.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,857,984 Swift, Jr. F May 10, 1932 2,045,771 Graham June 30, 1936 2,078,927 Dorr May 4, 1937 2,423,756 Chaplin July 8, 1947 2,600,130 Schilling June 10, 1952 

